2004 GMC SONOMA power steering

(A) Light Truck (LT-Metric) Tire:The United States
version of a metric tire sizing system. The letter “LT” as
the first two characters in the tire size means a light
truck tire engineered to standards set by the U. S. Tire
and Rim Association.
(B) Tire Width:The three-digit number indicates the
tire section width in millimeters from sidewall to sidewall.
(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example, if
the tire size aspect ratio is “75,” as shown in item “C” of
the illustration, it would mean that the tire’s sidewall is
75% as high as it is wide.(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire. The letter
“R” means radial ply construction; the letter “D” means
diagonal or bias ply construction; and the letter “B”
means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:The service description
indicates the load range and speed rating of a tire. The
load index can range from 1 to 279. Speed ratings
range from “A” to “Z”. The light truck tire size example
above shows dual or single tire configurations.Tire Terminology and Denitions
Air Pressure:The amount of air inside the tire pressing
outward on each square inch of the tire. Air pressure
is expressed in pounds per square inch (psi) or
kilopascal (kPa).
Accessory Weight:This means the combined weight
of optional accessories. Some examples of optional
accessories are, automatic transmission, power steering,
power brakes, power windows, power seats, and air
conditioning.
Aspect Ratio:The relationship of a tire’s height to its
width. Light Truck (LT-Metric) Tire
5-64

Fuse Usage
4 Gages, Body Control Module,
Instrument Panel Cluster
5 Parking Lamps, Power Window
Switch, Body Control Module,
Ashtray Lamp
6 Steering Wheel Radio Controls
7 Headlamps Switch, Body Control
Module, Headlamp Relay
8 Courtesy Lamps, Battery Run-Down
Protection
9 Heating, Ventilation, Air Cooling
Control Head (Manual)
10 Turn Signal
11 Cluster, Engine Control Module
12 Interior Lights
13 Auxiliary Power
14 Power Locks MotorFuse Usage
15 4WD Switch, Engine Controls (VCM,
PCM, Transmission)
16 Supplemental Inflatable Restraint
17 Front Wiper
18 Steering Wheel Radio Controls
19 Radio, Battery
20 Amplifier
21 Heating, Ventilation, Air Cooling
(Manual), Heating,Ventilation, Air
Cooling (Automatic), Heating,
Ventilation, Air Cooling Sensors
(Automatic)
22 Anti-Lock Brakes
23 Rear Wiper
24 Radio, Ignition
5-97

Part C: Periodic Maintenance
Inspections
Listed in this part are inspections and services which
should be performed at least twice a year (for instance,
each spring and fall).You should let your dealer’s
service department do these jobs. Make sure any
necessary repairs are completed at once.
Proper procedures to perform these services may be
found in a service manual. SeeService Publications
Ordering Information on page 7-11.
Steering, Suspension and Front
Drive Axle Boot and Seal Inspection
Inspect the front and rear suspension and steering
system for damaged, loose or missing parts, signs of
wear or lack of lubrication. Inspect the power steering
lines and hoses for proper hook-up, binding, leaks,
cracks, chafing, etc. Clean and then inspect the drive
axle boot seals for damage, tears or leakage. Replace
seals if necessary.
Exhaust System Inspection
Inspect the complete exhaust system. Inspect the body
near the exhaust system. Look for broken, damaged,
missing or out-of-position parts as well as open seams,
holes, loose connections or other conditions which
could cause a heat build-up in the floor pan or could let
exhaust fumes into the vehicle. SeeEngine Exhaust
on page 2-29.
Fuel System Inspection
Inspect the complete fuel system for damage or leaks.
Engine Cooling System Inspection
Inspect the hoses and have them replaced if they
are cracked, swollen or deteriorated. Inspect all pipes,
fittings and clamps; replace as needed. Clean the
outside of the radiator and air conditioning condenser.
To help ensure proper operation, a pressure test of
the cooling system and pressure cap is recommended
at least once a year.
6-30

Part D: Recommended Fluids and
Lubricants
Fluids and lubricants identified below by name, part
number or specification may be obtained from your
dealer.
Usage Fluid/Lubricant
Engine OilEngine oil which meets GM
Standard GM6094M and displays
the American Petroleum Institute
Certified for Gasoline Engines
starburst symbol. To determine the
proper viscosity for your vehicle’s
engine, seeEngine Oil on
page 5-13.
Engine Coolant50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
Coolant. SeeEngine Coolant on
page 5-23.
Hydraulic Brake
SystemDelco Supreme 11
®Brake Fluid or
equivalent DOT-3 brake fluid.
Windshield
Washer SolventGM Optikleen
®Washer Solvent.
Usage Fluid/Lubricant
Power Steering
SystemGM Power Steering Fluid (GM Part
No. U.S. 89021184, in Canada
89021186).
Automatic
TransmissionDEXRON
®-III Automatic
Transmission Fluid.
Key Lock
CylindersMulti-Purpose Lubricant, Superlube
®
(GM Part No. U.S. 12346241, in
Canada 10953474).
Chassis
LubricationChassis Lubricant (GM Part No.
U.S. 12377985, in Canada
88901242) or lubricant meeting
requirements of NLGI #2, Category
LB or GC-LB.
Front Wheel
BearingsWheel bearing lubricant meeting
requirements of NLGI #2, Category
GC or GC-LB (GM Part No. U.S.
1051344, in Canada 993037).
Front and Rear
Axle (Standard
Differential)SAE 80W-90 Axle Lubricant (GM
Part No. U.S. 1052271, in Canada
10950849).
6-32

F
Filter
Engine Air Cleaner......................................5-18
Finding a Program Type (PTY) Station...............3-52
Finding a Program Type (PTY) Station
(RDS and XM™).................................3-42, 3-63
Finding a Station....................3-37, 3-40, 3-50, 3-61
Finish Care....................................................5-90
Finish Damage...............................................5-92
Fixed Mast Antenna........................................3-76
Flash-to-Pass Feature....................................... 3-7
Flat Tire........................................................5-74
Flat Tire, Changing.........................................5-75
Fluid
Automatic Transmission................................5-19
Power Steering...........................................5-35
Windshield Washer......................................5-36
FM Stereo.....................................................3-74
Fog Lamps....................................................3-14
Following Distance..........................................4-61
Footnotes................................................6-7, 6-17
Four-Wheel Drive....................................2-22, 5-46
Front Axle......................................................5-47
Front Map Lamps...........................................3-15
Front Storage Area.........................................2-40Fuel............................................................... 5-4
Additives...................................................... 5-6
California Fuel.............................................. 5-5
Filling a Portable Fuel Container..................... 5-9
Filling Your Tank........................................... 5-7
Fuels in Foreign Countries.............................. 5-6
Gage.........................................................3-34
Gasoline Octane........................................... 5-4
Gasoline Specifications.................................. 5-5
Low Warning Light.......................................3-35
System Inspection.......................................6-30
Fuses
Fuses and Circuit Breakers...........................5-95
Windshield Wiper.........................................5-95
G
Gage
Check Gages Warning Light..........................3-34
Engine Coolant Temperature.........................3-28
Fuel..........................................................3-34
Oil Pressure...............................................3-32
Speedometer..............................................3-24
Tachometer.................................................3-24
Voltmeter Gage...........................................3-26
Garment Hooks..............................................2-40
6

Gasoline
Octane........................................................ 5-4
Specifications............................................... 5-5
Getting Familiar with Off-Road Driving................4-16
Glove Box.....................................................2-33
GM Mobility Program for Persons with
Disabilities.................................................... 7-5
H
Hazard Warning Flashers................................... 3-4
Head Restraints............................................... 1-6
Headlamp High/Low-Beam Changer.................... 3-7
Headlamps....................................................5-49
Bulb Replacement.......................................5-48
Electrical System.........................................5-95
Halogen Bulbs............................................5-48
One-Piece Front Turn Signal Lamps...............5-51
Two-Piece Front Turn Signal Lamps...............5-51
Heated Seats................................................... 1-4
Highway Hypnosis...........................................4-35
Hill and Mountain Roads..................................4-36
Hitches..........................................................4-59
Hood
Checking Things Under................................5-10
Release.....................................................5-10
Horn............................................................... 3-5
How to Add Automatic
Transmission Fluid.......................................5-22How to Add Coolant to the Coolant
Recovery Tank............................................5-30
How to Add Coolant to the Radiator..................5-32
How to Check................................................5-67
How to Check Lubricant..........................5-46, 5-47
How to Check Power Steering Fluid..................5-36
How to Check the Automatic
Transmission Fluid.......................................5-20
How to Inspect the Engine Air Cleaner/Filter.......5-18
How to Use This Manual...................................... ii
How to Wear Safety Belts Properly...................1-13
Hydroplaning..................................................4-31
I
If No Steam Is Coming From Your Engine..........5-27
If Steam Is Coming From Your Engine...............5-26
If the Light Is Flashing.....................................3-30
If the Light Is On Steady.................................3-30
If You Are Caught in a Blizzard.........................4-40
If You Are Stuck in Sand, Mud, Ice or Snow.......4-42
If You Do Decide To Pull A Trailer.....................4-56
Ignition Positions.............................................2-17
Ignition Transmission Lock Check......................6-28
Infants and Young Children, Restraints...............1-29
Inflation - Tire Pressure...................................5-67
Inspection
Brake System.............................................6-31
Engine Cooling System................................6-30
7

Locking Rear Axle............................................ 4-8
Lockout Protection..........................................2-10
Locks
Door........................................................... 2-7
Leaving Your Vehicle....................................2-10
Lockout Protection.......................................2-10
Power Door.................................................. 2-8
Programmable Automatic Door Locks............... 2-8
Rear Door Security Locks.............................2-10
Long Trip/Highway Definition.............................. 6-6
Long Trip/Highway Intervals............................... 6-6
Long Trip/Highway Scheduled Maintenance........6-17
Loss of Control...............................................4-13
Low Fuel Warning Light...................................3-35
Luggage Carrier..............................................2-40
Lumbar
Power Controls............................................. 1-4
M
Maintenance Schedule
At Each Fuel Fill.........................................6-25
At Least Four Times a Year..........................6-27
At Least Once a Month................................6-25
At Least Once a Year..................................6-27
At Least Twice a Year..................................6-26
Brake System Inspection..............................6-31
Engine Cooling System Inspection.................6-30
Exhaust System Inspection...........................6-30Maintenance Schedule (cont.)
Fuel System Inspection................................6-30
How This Section is Organized....................... 6-3
Introduction.................................................. 6-2
Long Trip/Highway Scheduled Maintenance.....6-17
Maintenance Requirements............................. 6-2
Normal Maintenance Replacement Parts.........6-34
Part A - Scheduled Maintenance Services......... 6-4
Part B - Owner Checks and Services.............6-25
Part C - Periodic Maintenance Inspections......6-30
Part D - Recommended Fluids and
Lubricants...............................................6-32
Part E - Maintenance Record........................6-36
Selecting the Right Schedule.......................... 6-5
Short Trip/City Scheduled Maintenance............. 6-6
Steering, Suspension and Front Drive Axle
Boot and Seal Inspection..........................6-30
Throttle System Inspection............................6-31
Transfer Case and Front Axle (Four-Wheel
Drive) Inspection......................................6-31
Using Your................................................... 6-4
Your Vehicle and the Environment................... 6-2
Maintenance When Trailer Towing.....................4-63
Making Turns.................................................4-61
Malfunction Indicator Light................................3-29
Manual Seats................................................... 1-2
Manual Windows............................................2-12
Manually Closing the Sunroof...........................2-43
Matching Transmitter(s) to Your Vehicle............... 2-5
9

Parking Brake and Automatic Transmission
Park (P) Mechanism Check...........................6-29
Parking on Hills..............................................4-62
Part A - Scheduled Maintenance Services............ 6-4
Part B - Owner Checks and Services................6-25
Part C - Periodic Maintenance Inspections..........6-30
Part D - Recommended Fluids and Lubricants....6-32
Part E - Maintenance Record...........................6-36
Passing.................................................4-11, 4-61
Passlock
®......................................................2-16
Payload.........................................................4-51
Pickup Conversion to Chassis Cab....................4-54
Plan Ahead When Possible................................ 7-7
Playing a Cassette Tape..................................3-54
Playing a CD.................................3-47, 3-57, 3-68
Playing a Specific Loaded CD..........................3-69
Playing the Radio...................3-36, 3-40, 3-49, 3-60
Power
Accessory Outlets........................................3-16
Door Locks.................................................. 2-8
Electrical System.........................................5-95
Lumbar Controls........................................... 1-4
Seat............................................................ 1-3
Steering Fluid.............................................5-35
Windows....................................................2-13
Power Steering................................................ 4-9
Programmable Automatic Door Locks.................. 2-8
Q
Questions and Answers About Safety Belts.........1-12
R
Radiator Pressure Cap....................................5-26
Radio Data System (RDS)...............3-39, 3-52, 3-59
Radio Messages.....................3-38, 3-44, 3-54, 3-65
Radios..........................................................3-35
AM-FM Radio.............................................3-36
Care of Your Cassette Tape Player................3-74
Care of Your CD Player...............................3-76
Care of Your CDs........................................3-75
Radio with Cassette and CD.........................3-49
Radio with CD............................................3-39
Radio with Six-Disc CD................................3-59
Setting the Time for Radios with Radio
Data Systems (RDS)................................3-36
Setting the Time for Radios without
Radio Data Systems (RDS).......................3-35
Theft-Deterrent............................................3-73
Understanding Reception..............................3-74
RDS Messages..............................3-43, 3-53, 3-64
11